Temp gauge runs all the way to the right, high coolant temp warning light comes on...why?

After a short time driving, the temp gauge runs high (up to 200 in less than 10 min). Eventually it redlined at 260, high coolant temp warning light came on, I pulled over a few times to let the temp drop. Little to no interior heat. My coolant level is good, no leakage, what could the problem be?

12 Answers

Thermostat stuck, water pump impellers, they may be plastic, don't know if your car has plastic impellers but they wear and can break, and will not leak... and no heat in the cabin indicates the coolant is not circulating. Either will cause that. Start with thermostat, that is the least expensive fix if that is what it is

There is an old sort of trick that you can put the thermostat in a pan of water on the stove, boil it and see if it opens, if you are really really on a tight budget, but they are not expensive, replace it regardless. If you have never done a thermostat be very careful, if it is not seated the housing will break. Spring side down in block. Don't over torque bolts. I am not dumbing it down for you, no offense intended. I don't know if you ever have. If that does not fix it, water pump is next like I said. And your'e welcome

Man alive, it could be a thermostat, but you need to completely flush the coolant and I'm not talking about just training it out, complete flush and clean, inspect all the hoses for spongy feeling hoses and the block and all the rest of the coolant system completely cleaned as it gets this gunk build up after a while and plugs up all the passages, then new Dexcool 50 50 ONLY as this is a GM and it's good stuff, and that GAowner club is driving me crazy, this is an Impala, lower the temperature of thermostat so it pops off sooner and check all the fins in your radiator for damage and if you see a bunch smashed in or bent up, there's a cheap little tool at Harbor Freight that you can buy and you run it through the damaged fins in the radiator allowing more air flow. Go from 180 degrees to 160 degree after the fact if your still having a problem which I doubt if you have a pro clean the coolant system professionally as they have a machine that force the coolant through all the ports and cleans all the gunk out. And if you need more detail let me know. I feel the 2004 and even still to today had a radiator that was to small. About a month ago I put a Whipple supercharger on a SS and we had over heating problems, changed to a larger radiator and a 160 degree thermostat drilled and it was perfect. That GAowner stuff is junk, this is W body car and a SS a that with a L67 the best engine ever made, why do you want to send if to some stupid Grand Am crap when he could go to RegalGS..org or more any forum for the SS period, do you get paid by the referral, I see it on every other post you make. Go to W body.com or 3800.com, you have a real car and I'm telling you this is common, Platform GM W platform Engine 3.4 L LA1 V6
3.8 L L36 V6 3.8 L L67 SC V6
Transmission 4-speed 4T65-E automatic 4-speed 4T65E-HD automatic, the wide bodies are all the same platform, just go to Wiki and search GM Wide body. But after you clean out your coolant., this is a bad A@#s car, love it,
In 2004 the Dale Jr. Edition came out, it was red in color and sported a black high sport kit. The number 8, with an “E” stripe design carried from the doors to the rear bumper. The 5 spoke diamond cut wheels featured a black stripe through each spoke and Dale Jr.’s signature appeared on the right side of the trunk lid. On the sides, the vehicle received Monte Carlo SS badges. Inside on the dash a #8 badge appeared and Dale Jr.’s signature on the cluster. This edition also got #8 floor mats and headrests. This was also the first nameplate car to receive GMs L67 Supercharged 3800 V6 engine.
To compete, the Intimidator Edition was re-released in 2004, this time, however the vehicle featured “Intimidator” badges on the trunk lid and both side panels of the vehicle. The car was all black in color, received the 5 spoke, diamond cut wheels and this time received GMs L67 Supercharged 3800 V6 engine.

Tenspeed has it right when air gets trapped in the water pump the impeller fins can no longer circulate the coolant. There is a bleeder screw by the water pump. Open it to let the air out of the system. Close it when coolant streams out of the bleeder screw. If that does not correct the problem you will need to flush your coolant system although that is rarely the problem.

I'm experiencing the same problem
on my 02 buick rendezvous cxl.. I
just replaced the thermostat this
morning, washed her and waxed her,
got her ready for a 45 min drive to
test her out and b4 she even got on
the highway my Guage slowly but
surely climbed to hot and "hot
coolant temp" is all u hear from the
dash.. could it be the coolant temp
sensor?

It could be a couple of things
depending on the condition and
miles and type of motor. It could be
caused by a faulty or shorted out
sensor it is common for them to fail
gm uses alot of diferent high amp
electronics its always good to check
and clean battery teminals wires bad
grounding or a weak battery can fry
the relays or sensors . but I've
noticed that it is a melted or dry
brittle broken wire some soldering
and shielding and your set. It may be
due for a coolant flush i dont know if
it still gm changed the formuala of
dexcool but it is infamous for
developing a sludge when antifreeze
levels are low it oxidises when
exposed to air and heat also it will
have a simillar reaction when mixed
with different types of antifreeze I
have done alot if coolant flushes and
repair work because some owner or
kid at jiffy lube put in the green stuff
instead of orange dexcool also is just
a rumor I've heard from other
mechanics but it may eat away and
shorten the life of plastic gaskets I
flush it out and use regular coolant
personally. Most likely though due to
the age and the motor designs
mostly the 3.4 it could have air
pockets in the system there can be
two to 3 different bleeder valves that
need to be opened to get all of the air
out properly. It could also be a stuck
thermostat and if its loosing coolant
most likely the lower intake gaskets
the water pump or worst case head
gaskets. Sometimes rare but I have
seen it happen with the 4t65e
transmission it could be the
transmission overheating and the atf
fluid could be causing it the
transmission cooler is built in to the
radiators of most gm models of
those years I personally install a
auxiliary trans fluid cooler in line with
the stock one.

Your Answer

Related Questions

After a short time driving, the temp gauge runs high (up to 200 in less than 10 min). Eventually it redlined at 260, high coolant temp warning light came on, I pulled over a few times to let the temp...

i'm interested in a 2001 Monte Carlo that has 128,000 miles car looks nice, my concern is that the temp gauge is inop, the person that owns the car said it was a 14.00 part but wasn't sure what the pa...

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use.